I’ve read posts about dead batteries from slow drains on models with secondary air....but my 2000 does not have it.

are there any other culprits that are almost always at fault?

doc

 

Air springs. The SLS (self-leveling suspension) system. If you're truck had air springs from the factory that were replaced by coil springs the amputated SLS system can drain the battery. The was the source of the parasitic drain in my truck that I spent a lot of time diagnosing several years ago, and the same is reported by several others here.

 

my 2000 Disco2 is an SD model; no air bags for sure. Springs only...

I am going to be NanoComing in a few days.

can I use it to turn that off IF it is active?

could it simply be the security system that is draining it?

thanks

doc

 

I think the process here is to put a multimeter between the negative battery terminal and the negative battery cable and start measuring amps once the truck has been sitting for 10-15 minutes - that'll show you the amperage draw on the battery while it's sitting. Then, you start pulling fuses until it drops down - then you start troubleshooting based on whatever that fuse is powering.

Using the negative side instead of the positive side is just a safety thing so you don't get a shock if the negative cable touches something else and grounds out.

 

I am planning on removing my Air Springs on my 04 Disco and replacing with a terrafirma 2" lift. What did you do to stop the battery drain?



Jon
2004 G4 Edition Discovery 2

 

I have this exact problem and I'm still working it out. There was a TSB about it a while back and quiescent current draw for the D2 should be no higher than 35mA, I would see spikes of 350mA on mine. Here's a troubleshooting method:
1) Open the hood and disconnect the hood alarm switch and roll down a window
2) Set a Multimeter to measure amps (you can switch it to mA later) and connect it in line with the negative battery post to a vehicle ground. This will cause any current being pulled by the truck to register on the multimeter. The TSB says to lock the truck with the Fob and wait up to a half hour for various systems to power down. My multimeter shuts off after 10 minutes so that's part of my problem.
3) Watch the current being drawn from the vehicle (switch your multimeter to mA).
4) If your truck is drawing too much power you can connect everything back up and proceed to the next step which is start pulling fuses and put your multimeter across the fuse box contacts to see what circuit is drawing the power.

On my truck it's fuse 2, which is the most complicated circuit on the truck (ECU, O2 sensors, etc.). I'm having a rear O2 sensor fault so I'm hoping that swapping those out will help. In the meantime I've installed a battery disconnect switch on the ground terminal, and honestly, for a vehicle that I only drive once a week- it's no problem to pop the hood before and after my outing (makes me check the coolant level too). so the power draw is low on my priority list to sort out.

 

I did this and found a bad relay in the engine compartment fuse box. It would kill my battery after few days of sitting. It also made my Disco have a couple bizarre electrical gremlins that completely went away when I replaced the relay.

 

What type (brand/model) are you using? I have one but have never tried to measure anything but simple voltage.. rotary **** style off a amazon...

 

I have a nice Fluke model that will track peak values, but any multimeter will do for this, just make sure the leads are in the right terminals for measure in current!